#include <iostream>
using namespace std;

int main()
{
    int l = 0, r = 1000;
    string res;
    while (l <= r) {
        int mid = l + r >> 1;
        cout << "? " << mid << endl;
        cin >> res;
        if (res == "<") {
            l = mid + 1;
        } else if (res == ">") {
            r = mid - 1;
        } else {
            cout << "! " << mid << endl;
            cin >> res;
            return 0;
        }
    }
}